56 results about "Feeding force" patented technology

The present application provides a kind of slotted equipment for coal seam gas control, belong to coal seam gas control technical field, including two slotted mainframes of synchronous coordination work, two slotted mainframes are arranged in the roadway of coal seam two sides respectively, and two slotted mainframes are driven connection through annular cutting cable between two slotted mainframes;Slotted mainframe includes self-propelled platform, power module, speed reducer, gear reversing device and main drive line wheel are set in self-propelled platform upper portion, power module passes through speed reducer and transmits power to gear reversing device;The present application uses annular cutting cable of cyclic motion as cutting force, and combines the feeding force provided by two slotted mainframes of synchronous coordination work, can cut out one or two slotted in coal seam transversely, instead of traditional high-density drilling, not only greatly reduces labor intensity, saves cost, and the permeability area formed by slotted is larger, more conducive to the desorption of gas, to greatly improve gas extraction efficiency.

The invention discloses a constant-linear-speed constant-pressure testing device and method for the wear resistance of an anchor rod drill bit for a coal mine. The testing device comprises a main shaft, a grinding wheel, and a constant-linear-speed control device, a displacement sensor and a constant-pressure automatic feeding device which are connected with an upper computer, the upper computer is used for setting the grinding linear speed and the grinding pressure required by the test standard and conducting PID parameter setting. The upper computer receives the radius of the grinding wheel acquired by the displacement sensor, calculates a grinding linear speed error and issues the grinding linear speed error to the constant linear speed control device to implement PID control; based on the radius abrasion loss of the grinding wheel, the pressurization feeding amount is adjusted; and the constant-pressure automatic feeding device is used for adjusting the grinding pressure required by the test standard according to the pressurization force by taking the grinding pressure error as the input of PID control during the period of adjusting the feeding amount. According to the invention, the linear speed control precision of the grinding wheel is not lower than 1%, and the fluctuation value of the feeding force does not exceed 0.5% of a set value.

The invention relates to a two-dimensional ultrasonic vibration device and a regulation and control method thereof. The two-dimensional ultrasonic vibration device comprises an ultrasonic vibration module, a loading vibration platform, a tool path track generation module and a control system module. The ultrasonic vibration module drives the platform to vibrate. And the control system module identifies characteristic parameters, calculates amplitude values required in the X direction and the Y direction according to the milling feeding direction, and transmits a control signal to the ultrasonic vibration module. The cutter path generating module generates a milling cutter path according to the size and the shape of a machined workpiece and generates a two-dimensional path diagram. Compared with an existing ultrasonic auxiliary machining device and method, the ultrasonic auxiliary machining device and method can actively follow the milling feeding direction and conduct ultrasonic vibration, the ultrasonic amplitude is always kept constant in the milling machining process, the ultrasonic vibration direction always follows the milling feeding direction, the milling feeding force is greatly reduced, the milling temperature is reduced, and the machining efficiency is improved. The workpiece machining quality is improved, and the machining efficiency is improved.

The utility model discloses a universal auxiliary feeding device for thin and thick materials and a sewing machine, relates to the technical field of sewing machines, and aims to solve the problem that an existing auxiliary feeding device is not high in applicability. The one-way clutch driving assembly comprises a one-way clutch driving star wheel shaft and a driven shaft, one end of the one-way clutch driving star wheel shaft is connected with a driving gear through a bearing and a bearing cover, a driven gear in meshing transmission with the driving gear is arranged on the driven shaft, and the tooth number of the driving gear is smaller than that of the driven gear. The two ends of the one-way clutch driving star wheel shaft and the two ends of the driven shaft are installed on the bearing installation bases, the bearing installation bases are fixed to the installation support, and the belt dragging wheel assembly is connected with the driven shaft, so that large cloth feeding force can be achieved for sewing of thin materials and thick materials, and the purpose that the thin materials and the thick materials are universal is achieved.

The invention relates to a cutting rock-breaking mechanism and a cutting method, and the cutting rock-breaking mechanism comprises a cutter assembly which comprises a sun gear rotating around a first axis; the planet gears are arranged at intervals in the circumferential direction, and eccentric structures are arranged on the planet gears; the planet wheel mandrel is sleeved with the planet wheel and rotationally connected with the planet wheel so as to bear inertia moment and / or radial inertia force which alternately rotates around the first axis; the planet carrier is coaxial with the first axis and is fixedly connected with the planet wheel mandrel; the cutterhead frame is connected with the planet carrier; when the planet carrier alternately rotates around the first axis, the cutter head frame reciprocates along the first axis and / or alternately rotates around the first axis; when the planet carrier swings in the radial direction, the cutterhead frame swings in the radial direction in a rotating mode. And the cutter is fixedly connected with the cutter head frame and has an eccentric distance. Rock is cut and broken under the multiple actions of extrusion feeding force of the cutter, vibration impact of the cutter and radial eccentric impact rock breaking, so that the rock breaking capacity (productivity) and the rock breaking efficiency are improved, the specific energy consumption of rock breaking is reduced, and the cutter is suitable for breaking hard rock.

The utility model discloses an automatic cleaning device for a feeding gear of an FDM 3D printer, and the automatic cleaning device comprises a feeder main body which is used for bearing all parts of a system; the material pressing wheel support is installed on the feeding machine body, a material pressing wheel is installed on the material pressing wheel support, pressure is continuously provided for the material pressing wheel through a material pressing spring, continuous feeding force is provided for consumables in cooperation with a feeding gear, and the printing requirement is met; the detection wheel support is provided with a detection wheel reset spring and a detection wheel, and the detection wheel is tightly meshed with the feeding gear all the time through the elastic force of the detection wheel reset spring; the photoelectric sensor is used for identifying whether the position of the detection wheel is normal; and the brush assembly is used for cleaning residues in the gap groove of the feeding gear. The situation that printing fails due to blockage and slipping of the feeding gear of the printer is effectively solved, meanwhile, the automatic cleaning device can effectively solve the problems of manual inspection and manual cleaning, personnel investment is reduced, and working efficiency is improved.

The invention relates to the technical field of motor shell machining, and discloses a cutting device for vibration motor shell machining, which comprises a cutting table, and further comprises an equipment box fixedly connected to the lower part of the cutting table and used for supporting the cutting table; the clamping mechanism is arranged in the equipment box and is used for clamping a machine shell; and the bottom of the cutting machine rotates around the machine shell on the cutting table through a rotating mechanism for cutting. By means of the rotating mechanism, constant initial feeding force is provided through the first tension spring, meanwhile, self-adaption of the cutting process is achieved through a one-way pawl mechanism composed of a deflector rod and a limiting hole with a rectangular bayonet, when the wall thickness is not uniform or casting defects occur, cutting counter-force can push the cutting machine to slightly retreat in the radial direction for buffering, and the cutting effect is good. And when the cutting condition is normal, the mechanism can lock and allow continuous feeding, knife pricking, tipping and even workpiece damage caused by sudden change of cutting force can be greatly avoided, and the mechanism is particularly suitable for machining characteristics of a vibration motor casting shell.

The special-shaped blank electromagnetic stirrer comprises a shell, an inductor is installed in the shell and comprises an iron core and coils, the iron core comprises a strip-shaped magnet yoke located in the shell, a plurality of magnetic poles are arranged on one side face of the magnet yoke, a plurality of coils are wound on the magnet yoke, and the coils are arranged on the side face of the magnet yoke. One end of the magnetic pole extends out of the shell, two ends of the upper bottom surface and the lower bottom surface of the magnet yoke are respectively provided with a mounting seat, and one end of each mounting seat extends out of the shell. The special-shaped blank electromagnetic stirrer can be oppositely installed on the two sides of a fan-shaped section of a special-shaped blank continuous casting machine, magnetic poles of the electromagnetic stirrer can penetrate through gaps between supporting rollers of the fan-shaped section, the magnetic poles are closer to flanges of special-shaped blanks, and therefore an effective magnetic field is close to casting blanks, the magnetic induction intensity of the casting blanks is improved, efficient traveling wave stirring is achieved, and the service life of the special-shaped blank continuous casting machine is prolonged. The feeding force of the casting blank can be improved through traveling wave stirring, the electromagnetic stirring action area is enlarged, and therefore the quality of the casting blank is improved.

The invention relates to an in-hole maintenance tool. The in-hole maintenance tool comprises a grinding mechanism and a recycling mechanism, the grinding mechanism comprises a feeding assembly and a grinding assembly, the feeding assembly is in driving connection with the grinding assembly, the feeding assembly provides feeding force for the grinding assembly to abut against a to-be-ground part, and the grinding assembly is used for grinding the to-be-ground part; the recovery mechanism and the polishing mechanism are integrated, the recovery mechanism comprises a recovery vessel, a dust collection conveying pipe and a dust collection driving part, one end of the recovery vessel is connected with the dust collection conveying pipe, the other end of the recovery vessel is connected with the dust collection driving part, and the dust collection conveying pipe is provided with a dust collection opening which is close to the polishing assembly; and the chippings are recovered into the recovery vessel through the dust collection opening and the dust collection conveying pipe in sequence. Through the arrangement, the efficiency of powerful dismantling work of the silver gasket is improved, the safety of the powerful dismantling work is guaranteed, repair of the sealing face is facilitated, and scrap pollution is avoided.

The invention provides a method and a system for controlling a flow drill screw based on volatility. A method of installing a flow drill screw (FDS) into a substrate includes engaging the FDS with an automated tool and operating the tool at a first setting to drive the FDS into the substrate. The first setting rotates the FDS at a first rotational speed and applies a first axial feed force. The first arrangement causes the substrate to flow to allow the FDS to penetrate through the substrate. The method includes detecting, via a sensor, axial position data of the FDS while operating the automated tool, and calculating, via a controller, a volatility of the axial position data. The method includes switching the automatic tool from the first setting to a second setting in response to the volatility. The second setting rotates the FDS at a second rotational speed and applies a second axial feed force to the FDS. The second rotational speed is less than the first rotational speed.

The utility model relates to the technical field of punching jigs, in particular to a sheet punching jig which comprises a mounting plate, a transmission assembly and a feeding assembly, a connecting plate is arranged on one side of the mounting plate, the transmission assembly is arranged on one side of the connecting plate, and the transmission assembly comprises a stepping motor, a driving gear, a first connecting rod, a driven gear and a transmission chain. The stepping motor is mounted on one side of the mounting plate through a first clamp and a screw, the output end of the stepping motor is connected with a driving gear, one end of the stepping motor is provided with a first connecting rod, and the top of the first connecting rod is connected with a driven gear; a feeding assembly is arranged between the transmission assembly and the mounting plate; the punching device is provided with a structure for stably transmitting the punching component in a chain transmission mode, feeding force can be provided for the punching component, and therefore the punching effect can be effectively improved.

A control system, rock drilling rig and method for controlling coupling measures is provided. The control system is arranged for controlling coupling and uncoupling measures of a threaded coupling of a rock drilling tool. The control system is configured to detect initial minimum feed force required for moving a rock drilling apparatus in forward direction and is configured to implement the detected minimum feed force during the coupling.

Sensor arrangement (1) and method for measuring contact feed force between a rock face (100) and a feed beam (5) of a mining or construction rig (50), which rig (50) comprises a boom (4) on which the feed beam (5) is arranged and which feed beam (5) is arranged to shuttle an object (40) back and forth along a feeding direction (Z) of the feed beam (5). The feed beam (5) comprises a rock engaging dowel (20c) at its first end (5a), for engaging the rock face (100), to stabilize the feed beam (5) during operation of the rig (50), wherein the sensor arrangement (1) comprises at least one force sensor, arranged to sense forces applied to the dowel (20c), wherein the at least one force sensor is arranged at the dowel (20c).

The invention relates to an intelligent self-adaptive extension device and method for a machine tool, and relates to the technical field of machine tool extension. Comprising an extension table, an anti-bending assembly is arranged in a fixing column, a pressing plate is fixed to one side of the anti-bending assembly, a centering positioning assembly is arranged in a placing table, a base is fixed to the top end of the centering positioning assembly, an adjusting assembly is arranged at the bottom of a placing plate, and a spring is fixed to one side of the adjusting assembly. The electric telescopic rod drives the moving block to slide, linear motion is converted into opposite sliding of the moving frame, then the sliding frame is pushed to drive the pressing plate to conduct opposite clamping through linkage of the rotating plate and the moving plate, vertical pressing of workpieces with different thicknesses can be adapted, cutting force, feeding force and vibration are effectively resisted, and the machining precision is improved. Warping, lifting or axial movement of the workpiece is avoided, cutting vibration marks are reduced, the surface machining quality of the workpiece is improved, and self-adaptive pressing of the workpieces with different thicknesses is achieved.

The application discloses a pile foundation sampling device for road and bridge construction and relates to the field of pile foundation sampling, which comprises a bottom plate, a drilling cylinder and a top block, the top block is located at the top end of the drilling cylinder, six plug-in grooves are uniformly arranged on the inner wall of the drilling cylinder, dehydration assemblies are inserted into the six plug-in grooves, the dehydration assemblies utilize the rotary power of the drilling cylinder and the axial feeding force of a sample core to remove water on the surface of the sample core, and the outer wall top end of the drilling cylinder is fixed with a first flange plate; a horizontal plate is movably sleeved on the outer wall of the top block through a bearing, and six arc-shaped positioning grooves are uniformly arranged on the lower surface of the top block, the application can realize simultaneous sampling and dehydration by utilizing the rotary power of the drilling cylinder and the axial feeding force of the sample core, can instantly scrape off water on the surface of the sample core and quickly pump out sewage in the drilling cylinder, so that the damage of water to the composition and structure of the sample core is avoided, and the accuracy of subsequent strength detection, composition analysis and other data is ensured.

The medium transport device includes a main roller configured to apply a feeding force to the medium in the transport direction, a pair of transport rollers includes a plurality of sub-rollers disposed at intervals along the longitudinal direction of the main roller, and being driven to rotate about a first shaft in a state where the medium is nipped between the sub-rollers and the main roller, and an adjustment section that adjusts a path difference between a first path and a second path when a path of the medium that is nipped and transported between the main roller and the plurality of sub-rollers is defined as the first path, and a path of the medium that is transported in contact with the main roller but not in contact with the plurality of sub-rollers 16 is defined as the second path.

The invention relates to the technical field of screw turning machining, in particular to bulking machine screw spindle machining equipment which comprises a machine tool, a follow rest used for assisting in supporting a workpiece is arranged on the machine tool, and a supporting mechanism used for limiting the machined face and the unmachined face of the workpiece at the same time is arranged on the follow rest. When the screw workpiece is roughly machined, the two abutting arms are used for limiting and supporting the two faces of the workpiece, so that the radial feeding force applied to the screw by a cutter can directly point to the follow rest, the supporting effect is guaranteed, and when the surface of the screw workpiece is finely machined, the workpiece can be precisely machined, and the machining precision of the workpiece is improved. The clamping wheel is controlled by the driving assembly to clamp the screw blade in a self-adaptive mode, tracking type axial limiting of the finish machining position of the cutter is achieved, position deviation of the screw due to axial pushing of the cutter in the finish machining process is effectively avoided, and the machining quality of the surface of the screw is guaranteed.

The invention relates to the technical field of plate fastening devices, in particular to a hot melting flow drilling system for connecting multiple layers of plates and a machining method.The hot melting flow drilling system comprises a hot melting self-tapping screw and a driving device, the hot melting self-tapping screw comprises a tapping part with threads outside, a screw cap and a drilling part, and the screw cap and the drilling part are arranged at the two ends of the tapping part respectively; the diameter of the screw cap is larger than that of the tapping part, the diameter of the drilling part is gradually reduced from the first end to the second end, and the first end of the drilling part is detachably connected to the tapping part through a connecting structure; the driving device is configured to be capable of grabbing a nail cap of the hot melting self-tapping screw and providing rotary driving force and axial feeding force for the nail cap of the hot melting self-tapping screw. The drilling part is detachably connected to the tapping part, after the upper-layer plate and the lower-layer plate are completely fastened by the hot-melting self-tapping part, the drilling part can be detached from the tapping part of the hot-melting self-tapping part, more space is vacated for assembling other parts, and the detached drilling part can be continuously recycled.

This invention relates to the field of drilling technology, specifically a quick-release drill bit for a drilling machine. It includes a connecting structure located at the bottom of the drilling machine and a drill bit structure located at the bottom of the connecting structure. The connecting structure is fixedly connected to the bottom of the drilling machine, while the drill bit structure is movably connected to the connecting structure, allowing for quick installation and removal of the drill bit structure within the connecting structure. The connecting structure includes a connecting cylinder located at the bottom of the drilling machine, which is fixedly connected to the drilling machine. A sliding cylinder is provided on the outer wall of the connecting cylinder, and the sliding cylinder is slidably connected to the outer wall of the connecting cylinder. This invention controls the radial extension and retraction of the stop block through the sliding cylinder, enabling quick locking and release of the drill rod with only one-handed push-pull operation. At the moment of drilling through the workpiece, the drill rod falls and automatically cuts off the feed force and torque, eliminating the risk of drill breakage due to a sudden increase in torque. Combined with an automatic upward sliding reset structure, it provides stable safety protection for the drill rod during continuous drilling cycles.

The invention provides a high-strength laser pressure welding method which is executed by a system comprising a servo pressing driving mechanism and a laser galvanometer assembly of which the tail end is integrated with a rigid coaxial pressing nozzle. The method comprises the following steps that (1) a servo pressing driving mechanism is controlled to drive a laser galvanometer assembly to feed downwards in the Z-axis direction till the end face of a rigid coaxial pressing nozzle abuts against the surface of a workpiece; after contact, an axial feeding force is continuously applied to a preset pressure and a stroke threshold value; and (2) the servo pressing driving mechanism is kept in a position locking or torque keeping state so as to maintain constant mechanical pressing force, the laser galvanometer assembly is triggered to emit light, the laser beam is controlled to scan a C-shaped welding track within the range of the inner hole of the nozzle, and the C-shaped welding track is a non-closed curve and is not coincident in head and tail. According to the method, the C-shaped non-closed track is adopted, compared with a traditional O-shaped track, the C-shaped opening provides a stress release channel, closing of circumferential tensile stress is effectively blocked, and the welding crack sensitivity of the high-strength steel is greatly reduced.

The automatic pencil feeding structure of the pencil sharpener comprises a mounting base and a driving part, a base through hole for the driving part to be plugged in is formed in the mounting base, a pencil hole with two through ends for a pencil to be inserted in is formed in the driving part, base inner teeth are arranged on the inner wall of the base through hole, and a flexible gear outer tooth ring is arranged in the base inner teeth in a sleeved mode. The flexible gear outer gear ring is arranged on the driving part in a sleeving mode, the driving part is sleeved with a steel wheel rotating disc, a circle of rotating disc outer teeth are arranged on the outer side face of the steel wheel rotating disc, rotating disc inner teeth connected to the flexible gear ring in a meshed mode are arranged on the inner side of the steel wheel rotating disc, two shaft rods are rotationally installed on the outer side of the installation base in parallel, and a pen skin feeding wheel and a small gear are installed on the shaft rods. The pinions are connected to the outer teeth of the rotary disc in a meshed mode, the two pinions are installed in a staggered mode, and a pencil feeding space is formed between the two pencil feeding leather wheels. The pencil feeding structure has the advantages that through simple parts, the ultrahigh reduction ratio is achieved, the pencil feeding force is reduced, abrasion to a pencil is reduced, and the service life of the pencil feeding structure is greatly prolonged.

A method for controlling a drilling apparatus (4), configured to perform a drilling operation in which said drilling apparatus breaks a mineral substrate (20). The drilling apparatus comprises a feed beam (6), a cradle (8), movable along the feed beam, and a drilling equipment (10). The drilling equipment comprises a hammer piston assembly (12), comprising a piston (13), wherein the hammer piston assembly is connected to the cradle, and a fluid supply system, configured to supply a fluid to said hammer piston assembly. The fluid supply system comprises an outlet, configured to release fluid from the fluid supply system during the drilling operation, and an evacuation valve, configured to release fluid from the fluid supply system when the evacuation valve is open. The method comprises controlling the drilling apparatus to perform the drilling operation, wherein the cradle moves towards the mineral substrate such that a feed force is applied towards said mineral substrate, and the fluid supply system moves the hammer in a series of reciprocating strokes. The method further comprises controlling the cradle to move away from the mineral substrate such that the drilling operation is interrupted. The method further comprises controlling the evacuation valve to open prior to moving the cradle away from the mineral substrate.

The present application relates to the technical field of screw turning processing, in particular to a bulking machine screw spindle machining equipment, which comprises a machine tool, a follow rest for assisting in supporting a workpiece is arranged on the machine tool, a supporting mechanism for limiting the machined surface and the unprocessed surface of the workpiece at the same time is arranged on the follow rest, and an anti-channeling mechanism for axially assisting in limiting the workpiece is further arranged on the follow rest, the present application adopts double-face limiting and supporting of the workpiece by two abutting arms when the screw workpiece is rough machined, so that the radial feeding force of the cutter applied to the screw can be directly pointed to the follow rest, and the supporting effect is ensured, when the screw workpiece surface is finish machined, the driving assembly controls the self-adaptive clamping of the screw blade by the clamping wheel, the tracking type axial limitation of the cutter finish machining position is realized, the position deviation of the screw caused by the axial pushing of the cutter in the finish machining process is effectively avoided, and the machining quality of the screw surface is ensured.

This invention relates to the field of hydraulic motor technology and discloses a hydraulic motor-driven feeding mechanism, including a drive motor device body. A fixed housing is fixedly connected to the top of the drive motor device body, and an internally threaded tube is fixedly installed at the bottom inside the fixed housing. A threaded post is connected to the internal threads of the internally threaded tube. This hydraulic motor-driven feeding mechanism, by setting a first gear, a second gear, and a threaded post, utilizes the threaded connection between the threaded post and the internally threaded tube to allow the connecting post to rise and fall smoothly. The first gear has more teeth than the second gear. Therefore, during the rising and falling of the threaded post, when the main meshing gear on the output shaft surface contacts and rotates with the first or second gear, the rotational speed of the main meshing gear slows down or speeds up, resulting in a stronger or weaker rotational meshing force. This achieves the purpose of adjusting the feeding force, facilitating the conveying of materials of different weights.

This invention discloses a multi-directional force fusion sensing system for an ultrasonic drilling three-jaw chuck. The three-jaw chuck has a first base jaw slide, a second base jaw slide, and a third base jaw slide evenly distributed along its circumference. A clamping force monitoring module is detachably mounted on the first base jaw slide, an axial feed force monitoring module is detachably mounted on the second base jaw slide, and a cutting torque monitoring module is detachably mounted on the third base jaw slide. When clamping the workpiece, the workpiece clamping surface abuts against the clamping force monitoring module, the axial feed force monitoring module, and the cutting torque monitoring module. By having the three monitoring modules directly abut against the workpiece clamping surface and bottom end while the workpiece is clamped, the sensor placement is moved forward to near the machining deformation zone, shortening the force signal transmission path, avoiding high-frequency noise pollution from ultrasonic vibration on the sensor signal, improving the signal-to-noise ratio and anti-interference capability of the monitoring system, and solving the problems of low measurement accuracy and high false alarm rate caused by the long signal path and the distance of sensors from the machining area in traditional monitoring methods.

The application belongs to the field of hydraulic forming of pipe fittings, and specifically discloses an electromagnetic impact hydraulic forming device and method for pipe fittings. After the relative spatial positions of the pipe fitting, the driving plate and the punch are uniquely designed, the same driving coil simultaneously generates axial electromagnetic forces on the driving plate and the high-conductivity metal pipe fitting at the upper end, respectively, the axial electromagnetic force generated on the driving plate further generates internal fluid pressure inside the pipe fitting, radial expansion of the pipe fitting is realized, the axial electromagnetic force generated at the end of the high-conductivity metal pipe fitting further generates an axial feeding force at the end of the pipe fitting, axial material flow is realized, and the coordinated high-speed driving of the radial expansion of the pipe fitting and the axial material flow effectively suppresses the problem of the thinning of the wall thickness of the pipe fitting. Since the internal pressure supply system and the end feeding control system are removed, the problem that the existing traditional pipe fitting hydraulic forming technology relies on an internal hydraulic power source and an external control system and that it is difficult to match and control the internal pressure and the axial feeding is solved.

The application discloses a wire cutting equipment with automatic threading function and a use method thereof, and relates to the technical field of wire cutting machines.The wire cutting equipment comprises a wire cutting assembly for threading processing, and the wire cutting assembly comprises a base, a wire winding and unwinding part arranged on one side of the top of the base, a wire tensioning part arranged on one side of the wire winding and unwinding part, and a turning guide wheel arranged on one side of the wire tensioning part.In the threading operation, the cylinder pushes the rotating support to close the guide wheel, so that the curled, upturned and crooked end of the molybdenum wire can be automatically scraped, straightened and aligned, the curled end is prevented from blocking the conveying pipe and causing threading failure, the double guide wheels are clamped and the wire is fed in synchronization with the driving and driven gears, the feeding force is uniform, the molybdenum wire is smoothly conveyed, the threading and cutting modes are switched only by the extension and retraction stroke of the cylinder, the straightening cylinder is opened and closed in synchronization, the air blowing flow is strong and weak, the oil absorbing cotton is attached in different states, the lubricating oil circuit is connected and disconnected, the corrosion resistance and anti-interference capability are high, and the post-maintenance is simple.

To suppress occurrence of wrinkles of a medium caused by a path difference between a first path and a second path.SOLUTION: A medium conveying device 3 comprises: a conveying roller pair 10 that has a main roller 14 that applies feeding force toward a conveying direction to a medium 2 and a plurality of sub rollers 16 that followingly rotates around a first shaft 15 while gripping the medium in pair with the main roller and are arranged with an interval from each other along a longitudinal direction of the main roller; and an adjusting part 19 that adjusts a path difference between a first path 17 and a second path 18, where a path on which the medium 2 is conveyed while being gripped between the main roller and the sub rollers is defined as the first path, and a path on which the medium is conveyed while being contacted with the main roller without being contacted with the sub rollers is defined as the second path.SELECTED DRAWING: Figure 3

The utility model discloses a branch-cutting machine for forest land, which belongs to the technical field of branch-cutting machines and is characterized in that a hydraulic chain saw is fixed on a support arm, the support arm is connected to a telescopic arm through a shaft, the angle of the support arm is adjusted by starting a support arm working cylinder, and the hydraulic chain saw runs at a high speed during operation; the supporting arm working cylinder acts to provide feeding force for the hydraulic chain saw to complete branch sawing operation, the protection plate is installed on the hydraulic chain saw to protect the operation monitoring camera, the monitoring camera is used for assisting an operator of the branch cutting machine to observe the operation condition, and the whole machine is simple in structure, easy to operate, stable in equipment performance, good in cutting performance and high in practicability. And the adopted hydraulic chain saw has the advantages of being stable in performance, high in power mass ratio, adjustable in rotating speed, high in adaptability and the like, the production efficiency is high, good practicability is achieved when the hydraulic chain saw works in the environment such as forest land, and certain economic benefits and social benefits can be generated.